Question

Which coordinates are not of the vertices of the feasible region for the system of inequalities?

Answer 1

$\left\{\begin{array}{ccc}y \ \textless \ 4\\x \ \textless \ 5\\x+y \ \textgreater \ 6\end{array}\right\\\\A.\ (5;\ 1)\to x=5\ and\ y=1\to x=5\ it's\ not\ less\ 5\\\\B.\ (0;\ 6)\to x=0\ and\ y=6\to y=6\ it's\ not\ less\ 4\\\\C.\ (2;\ 4)\to x=2\ and\ y=4\to x+y=2+4=6\ it's\ not\ greater\ 6\\\\D.\ (5;\ 4)\to x=5\ and\ y=4\to x=5\ it's\ not\ less\ 5\ and\ y=4\ it's\ not\ less\ 4$

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